Patent US4613522A successfully refreshed from Google Patents.
US4613522A
Expired / Lapsed
US
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Oxidation resistant carbon-carbon composites
Assignee: Avco Corp
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Filing: 1982-09-29
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Granted: 1986-09-23
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Expires: 2002-09-29
Abstract
Abstract An oxidation resistant carbon-carbon composite (31) including a plurality of graphite fibers (13) within a carbonized (graphitized) matrix (14). A first material including boron (16) and a second material including silicon (18) are applied thereto. Heating the composite in the course of service use to a temperature at which the composite cracks enables the boron and silicon to combine to provide a borosilicate sealant of sufficiently low viscosity for sealing cracks in the composite.
Inventors
- 👤 Thomas Vasilos
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 22:35
CPC Classifications
B; B32; B32B; B32B5/00; B32B5/22; B32B5/30; C; C03; C03C; C03C14/00; C03C14/002; B32B5/16; C04; C04B; C04B35/00; C04B35/71; C04B35/78; C04B35/80; C04B35/83; C04B41/00; C04B41/009; C04B41/45; C04B41/50; C04B41/5022; C04B41/80; C04B41/81; C04B41/85; C04B41/86; B32B2260/00; B32B2260/02; B32B2260/021; B32B2260/04; B32B2260/046; B32B2262/00; B32B2262/10; B32B2262/106; B32B2264/00; B32B2264/10; C03C2214/00; C03C2214/02
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
138 words
Method for making an oxidation resistant carbon fiber array-reinforced-carbon matrix composite comprising: impregnating each one of a number of the carbon fiber array with a resin matrix capable of being converted to a carbon matrix to constitute a preform, distributing a first material comprising boron or material containing boron in particulate form throughout the resin matrix, heating said preform to 650° C. to carbonize said resin matrix, and heating said preform to between 2000° C. and 2300° C. to graphitize said resin matrix, vaporize said first material and disperse said first material throughout said composite, applying a second material including silicon to said array, whereby heating said composite to a temperature at which said composite cracks enables said boron and silicon to combine to provide a borosilicate sealant of sufficiently low viscosity for sealing cracks in said composite.
Claim 2
Dependent Claim
138 words
Method for making an oxidation resistant carbon fiber array-reinforced-carbon matrix composite comprising: impregnating each one of a number of the carbon fiber array with a resin matrix capable of being converted to a carbon matrix to constitute a preform, distributing a first material comprising boron or material containing boron in particulate form throughout the resin matrix, heating said preform to 650° C. to carbonize said resin matrix, and heating said preform to between 2000° C. and 2300° C. to graphitize said resin matrix, vaporize said first material and disperse said first material throughout said composite, applying a second material including silicon to said array, whereby heating said composite to a temperature at which said composite cracks enables said boron and silicon to combine to provide a borosilicate sealant of sufficiently low viscosity for sealing cracks in said composite.
Claim 3
Dependent Claim
22 words
Method in accordance with claim 1 including arranging said fiber array in layers and applying said first material between each said layer.
Claim 4
Dependent Claim
22 words
Method in accordance with claim 2 including coating said second material on the exterior surfaces of said resin impregnated and graphitized array.
Claim 5
Dependent Claim
13 words
Method in accordance with claim 1 wherein said first material includes boron carbide.
Claim 6
Dependent Claim
14 words
Method in accordance with claim 1 including disposing said first material in said matrix.
Claim 7
Dependent Claim
19 words
Method in accordance with claim 1 further including sprinkling said first material in particulate form on said fiber array.
Claim 8
Dependent Claim
13 words
Method in accordance with claim 1 wherein said second material includes silicon carbide.
Claim 9
Dependent Claim
16 words
Method in accordance with claim 1 further including compression bonding said impregnated plies prior to heating.
Claim 10
Dependent Claim
24 words
Method in accordance with claim 1 further including heating said preform between 65° C. and 175° C. to cure said preform prior to carbonization.
Claim 11
Independent Claim
79 words
A method of constructing a self-healing carbon structure comprising the steps of: dispersing boron in particulate form or a material containing boron on the carbon by heating said composite above 2000° C. to vaporize the boron; encapsulating the carbon-boron composite with a silicon-containing coating; and heating said composite to a temperature at which said composite cracks to enable said boron and silicon to combine to provide a borosilicate sealant of sufficiently low viscosity for sealing cracks in said composite.
Claim 12
Independent Claim
79 words
A method of constructing a self-healing carbon structure comprising the steps of: dispersing boron in particulate form or a material containing boron on the carbon by heating said composite above 2000° C. to vaporize the boron; encapsulating the carbon-boron composite with a silicon-containing coating; and heating said composite to a temperature at which said composite cracks to enable said boron and silicon to combine to provide a borosilicate sealant of sufficiently low viscosity for sealing cracks in said composite.
Claim 13
Dependent Claim
18 words
Method of making a self-healing carbon structure as defined in claim 10 wherein the borosilicate is a glass.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-22 | 1990-03-24 | 1990-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-22 | 1994-03-24 | 1994-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-22 | 1998-03-24 | 1998-09-23 | $7700.00 | Window Closed / Lapsed |